U.S. patent number 4,590,398 [Application Number 06/657,400] was granted by the patent office on 1986-05-20 for brush holder.
This patent grant is currently assigned to Kabushiki Kaisha Yaskawa Denki Seisakusho. Invention is credited to Toshio Nagamatsu.
United States Patent |
4,590,398 |
Nagamatsu |
May 20, 1986 |
Brush holder
Abstract
A brush holder comprising a brush box and a brush terminal. The
brush box includes a brush sliding tube which is mounted at
opposite upper sides thereof with a pair of side plates. Each of
the side plates forms a clearance and has an upper opening and a
lower opening. The brush terminal has a pair of bent pieces and a
central portion therebetween for connecting a pigtail. An engaging
projection is formed on the bent pieces. The engagement and
fixation between the brush box and the brush terminal are performed
outside of the brush box, with the engaging projection coupling to
the lower opening, and the bent pieces inserted into the
clearance.
Inventors: |
Nagamatsu; Toshio (Iruma,
JP) |
Assignee: |
Kabushiki Kaisha Yaskawa Denki
Seisakusho (Fukuoka, JP)
|
Family
ID: |
11826846 |
Appl.
No.: |
06/657,400 |
Filed: |
October 3, 1984 |
Foreign Application Priority Data
|
|
|
|
|
Feb 3, 1984 [JP] |
|
|
59-13212[U] |
|
Current U.S.
Class: |
310/239; 29/597;
310/71 |
Current CPC
Class: |
H01R
39/40 (20130101); Y10T 29/49011 (20150115) |
Current International
Class: |
H01R
39/00 (20060101); H01R 39/40 (20060101); H02K
013/00 () |
Field of
Search: |
;310/239,240,241,242,244,245,246,247,71,248,249,42 ;29/597 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
2712721 |
|
Sep 1978 |
|
DE |
|
2110833 |
|
Jun 1983 |
|
GB |
|
Primary Examiner: Skudy; R.
Attorney, Agent or Firm: Ladas & Parry
Claims
What is claimed is:
1. A brush holder comprising:
a brush box including a brush sliding tube, said brush sliding tube
being mounted at opposite upper sides thereof with a pair of side
plates, each of said side plates forming a clearance and having an
upper opening and a lower opening; and
a brush terminal bent to form a generally U-shaped section having
an upper opening and having a pair of bent pieces at opposite ends
and a central portion therebetween for connecting a pigtail, at
least one of said pair of bent pieces being provided with an
engaging projection, said projection opening to the outside of said
brush sliding tube, and one of said pair of bent pieces being
partially cut and extended to form an electrical contact, said
brush teminal is fixed to said brush box such that said pair of
bent pieces are inserted into said clearances at the opposite sides
of said brush sliding tube, and that said engaging projection of
said bent pieces is engaged with said lower opening of each of said
side plates.
2. A brush holder as set forth in claim 1, in which said lower
opening of said side plate is formed in lower portion of said side
plate.
3. A brush holder as set forth in claim 1 or 2, in which outer
surfaces of said pair of bent pieces contact under pressure with
inner surfaces of said pair of side plates.
4. A brush holder as set forth in claim 1, in which dimension of
said clearance is larger than that, in a direction of thickness, of
said engaging projection of at least one of said bent pieces.
5. A brush holder as set forth in claim 3, in which dimension of
said clearance is larger than that, in a direction of thickness, of
said engaging projection of at least one of said bent pieces.
Description
BACKGROUND OF THE INVENTION
1. Field of the technique
The present invention relates to a brush holder which is applied to
a small size electric motor or other devices.
2. Prior art
One example of a prior art brush holder of a small size is
disclosed in Japanese Utility Model Publication No. 56-31166. FIG.
1 is a disassembled perspective view of the brush holder shown in
the Publication, and FIG. 2 is a sectional view illustrating a main
part of the brush holder of FIG. 1 after it is assembled. In the
figure, reference numeral 101 denotes a brush box, numerals 101a
and 101b denote slits formed at opposite sides of the brush box 101
and numeral 103 denotes a top plate including bent pieces 103c and
103d opposing to each other which are to be inserted into the brush
box 101, the bent pieces 103c and 103d being provided with nails
103a and 103b capable of engaging with the slits 101a and 101b.
Numeral 107 denotes a solder portion connecting a pigtail 104 and
the top plate 103. Numerals 102 and 105 denote a brush and a brush
spring, respectively.
With the structure as above, the top plate 103 is fixed to the
brush box 101 by engaging the nails 103a and 103b of the top plate
3 with the slits 101a and 101b of the brush box 101.
In the prior art brush holder, a brush terminal 103 (top plate)
formed by bending is directly inserted for fixation thereof within
the interior of the brush box 101 constituting a sliding surface
for the brush 102, so that the upper end of the brush spring 105
locates at the position lower than the upper end of the brush box
101. Therefore, the brush box must cover this additional length
beside that for the brush 102, which results in a longer brush
holder. It is a problem for miniaturization of an electric
motor.
Further, in the prior art brush holder, the longer the height of
the bent pieces 103c and 103d of the brush terminal 103, the easier
the bending operation of the opposing side portions and the
insertion of the brush terminal 103 into the brush box 101 become.
However, this seriously leads to the above problem that the length
of the brush box becomes larger. Thus, it is necessary to shorten
the length of the height. However, a larger force is required to
bend the opposing sides or the nails 103a and 103b. It becomes
difficult to insert the brush terminal 103 into the brush box
101.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to overcome the
prior art problems and to provide a brush holder with a simple
structure which can be assembled with ease and certainty.
The brush holder of the present invention comprises (1) a brush box
including a brush sliding tube, the brush sliding tube being
mounted at opposite upper sides thereof with a pair of side plates,
each of the side plates forming a clearance and having an upper
opening and a lower opening; (2) a brush terminal bent to form a
generally U-shaped section having an upper opening and having a
pair of bent pieces at opposite ends and a central portion
therebetween for connecting a pigtail; and (3) an engaging
projection formed on at least one of the pair of bent pieces,
wherein the brush terminal is fixed to the brush box such that the
pair of bent pieces are inserted into the clearances at the
opposite sides of the brush sliding tube, and that the engaging
projection of the bent pieces is engaged with the lower
opening.
The above object, other objects and advantages of the present
invention may be readily ascertained by referring to the following
description and appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a disassembled perspective view of a prior art brush
holder;
FIG. 2 is a sectional view of the brush holder shown in FIG. 1
after it is assembled;
FIGS. 3 to 5 are views of the brush connecting structure according
to one embodiment of the present invention, showing a plan view,
side view of the structure, and a perspective view of the brush
terminal, respectively;
FIG. 6 is a sectional side view of the brush box in which the brush
connecting structure is accommodated and assembled;
FIG. 7 is a sectional side view of the embodiment of the brush
holder according to the present invention; and
FIG. 8 is a sectional side view of another embodiment of the brush
holder according to the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
One embodiment of the present invention is now described.
FIG. 3 is a plan view of a brush connecting structure, FIG. 4 is a
side view of the structure, and FIG. 5 is a perspective view of the
brush terminal of the structure. A brush terminal is bent to form a
generally U-shaped section having an upper opening 15 and has a
pair of bent pieces 10 at opposite ends and a central portion
therebetween for connecting a pigtail 4. One of the bent pieces 10
is partially cut and extended to form an electrical contact 1, and
the other of the bent pieces 10 is also partially cut out so that
flexibility for both bent pieces 10 may substantially be balanced
and maintained equal. Further, at the same time, engaging
projections 2 are formed.
A brush 5 is connected to the brush terminal and to the solder
connecting portion 12 through the pigtail 4. Numeral 3 denotes a
brush spring.
FIG. 6 is a sectional side view of the brush connecting structure
in which a brush box is accommodated and is assembled.
The brush box or brush holder includes a brush sliding tube 6 at
opposite upper sides thereof. Each of the side plates 9 forms a
clearance 11 and has an upper opening 8 and a lower opening 7. The
side plates 9 are made integrally with the brush sliding tube
6.
The side plates 9 and the brush sliding tube 6 are made of, for
instance, a synthetic resin, and are molded into an integral
member. The lower opening 7 is not provided in the entire
circumference, but is provided in one part of each side plate 9.
The sectional areas of the tube 6 and the side plates 9 are
protions of the same member.
FIG. 7 is a sectional view of an embodiment of the brush
holder.
The pair of bent pieces 10 are inserted into the clearances 11 at
the opposite sides of the brush sliding tube 6, and the engaging
projections 2 on the bent pieces 10 are engaged with the lower
openings 7 formed in the side plates 9. Thus, the brush terminal is
fixed to the brush box. The engaging projections 2 are extending or
opening to the outside of the brush sliding tube 6.
FIG. 8 is a sectional side view of another embodiment according to
the present invention.
In this embodiment, lower openings 7 are formed in side plates 9
mounted at opposite sides of a brush sliding tube and are formed by
cutting out marginal portions 71 shown in FIG. 7.
The following modifications may be thought of as other embodiments
of the present invention. (1) Instead of using the engaging
projection of a semispindle shape as shown in FIG. 5, other
configurations such as of the nails 103a and 103b shown in FIG. 2
may also be employed. (2) The dimension of the clearance formed by
the brush sliding tube 6 and the side plate 9 is made larger than
that, in a direction of thickness, of the engaging projection 2 of
the bent piece 10.
As seen from the above description, the following effects can be
obtained from the present invention, which are beneficial in the
field of this technology.
(1) Since the engagement and fixation between the brush terminal
and the brush box are carried out outside of the brush sliding
tube, the whole length of the brush sliding tube can be used for
supporting the brush so that the brush box is made shorter in
length. Thus, it is effective in that the motor may be
miniaturized.
(2) Since the engagement and fixation between the brush terminal
and the brush box are carried out outside of the brush sliding
tube, the length of the bent pieces of the brush terminal can be
shortened. Therefore, the insertion of the bent pieces into the
clearance aside of the brush box becomes easy, and the fixation of
the brush terminal to the brush box becomes simple.
Having described specific embodiments of the present invention, it
should be understood that modification and variation of the
invention are possible in light of the above teaching.
* * * * *